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Davies KJ, Kerslake ID, Walters J, Thomas MJ. Survival benefit for patients receiving antibiotics following out-of-hospital cardiac arrest. Crit Care 2012. [PMCID: PMC3363694 DOI: 10.1186/cc10883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Jackson RJ, Gould TH, Thomas MJ. Worst Oxygenation Index during the first 24 hours of ventilation predicts mortality. Crit Care 2012. [PMCID: PMC3363508 DOI: 10.1186/cc10697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
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Moriarty KM, Thomas MJ. Failure to Induce Contact Hypersensitivity in the Opossum, Ittrichosurus Vulpecula. N Z Vet J 2011; 30:160. [PMID: 16030830 DOI: 10.1080/00480169.1982.34924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Moriarty KM, Thomas MJ. Cell-mediated immunity in opossums(Trichosurus Vulpecula): The responses to purified protein derivative and an unrelated antigen. N Z Vet J 2011; 31:63-4. [PMID: 16030960 DOI: 10.1080/00480169.1983.34970] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Cook SC, Gatward JJ, Kelly FE, Bell J, O'Higgins FM, Thomas MJ. Simulation training at the point of care to decrease the incidence of airway complications on the intensive care unit. Crit Care 2010. [PMCID: PMC2934094 DOI: 10.1186/cc8695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Whitby M, Gordon RD, Seeney N, Thomas MJ. Vasectomy: a long-term study of its effects on testicular endocrine function in man. Andrologia 2009; 8:55-9. [PMID: 952419 DOI: 10.1111/j.1439-0272.1976.tb01647.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Plasma testosterone, luteinizing hormone (L.H.) and follicle stimulating (F.S.H.) were measured before operation in 39 males, aged 26 to 53 years with 2 to 5 children, seeking vasectomy for contraceptive purposes. These measurements were repeated at 3 and 12 months after vasectomy. Levels of L.H. at 12 months were significantly higher than pre-vasectomy levels, suggesting some degree of decreased Leydig cell function. However, testosterone and F.S.H. levels were similar at the three sampling times. Continuing yearly measurements for at least 5 years are planned.
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Philipraj SJ, Thomas MJ, Gopalakrishnan G. Immediate or early alignment versus delayed management for posterior urethral injuries. Hippokratia 2009. [DOI: 10.1002/14651858.cd005404.pub3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Philipraj SJ, Thomas MJ, Gopalakrishnan G. Immediate or early alignment versus delayed management for posterior urethral injuries. Hippokratia 2008. [DOI: 10.1002/14651858.cd005404.pub2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Thomas MJ, Kalivas PW, Shaham Y. Neuroplasticity in the mesolimbic dopamine system and cocaine addiction. Br J Pharmacol 2008; 154:327-42. [PMID: 18345022 PMCID: PMC2442442 DOI: 10.1038/bjp.2008.77] [Citation(s) in RCA: 323] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 12/11/2007] [Accepted: 02/13/2008] [Indexed: 02/08/2023] Open
Abstract
The main characteristics of cocaine addiction are compulsive drug use despite adverse consequences and high rates of relapse during periods of abstinence. A current popular hypothesis is that compulsive cocaine use and cocaine relapse is due to drug-induced neuroadaptations in reward-related learning and memory processes, which cause hypersensitivity to cocaine-associated cues, impulsive decision making and abnormal habit-like learned behaviours that are insensitive to adverse consequences. Here, we review results from studies on the effect of cocaine exposure on selected signalling cascades, growth factors and physiological processes previously implicated in neuroplasticity underlying normal learning and memory. These include the extracellular signal-regulated kinase (ERK) signalling pathway, brain-derived neurotrophic factor (BDNF), glutamate transmission, and synaptic plasticity (primarily in the form of long-term potentiation and depression, LTP and LTD). We also discuss the degree to which these cocaine-induced neuroplasticity changes in the mesolimbic dopamine system mediate cocaine psychomotor sensitization and cocaine-seeking behaviours, as assessed in animal models of drug addiction. Finally, we speculate on how these factors may interact to initiate and sustain cocaine psychomotor sensitization and cocaine seeking.
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Baskin CR, Bielefeldt-Ohmann H, García-Sastre A, Tumpey TM, Van Hoeven N, Carter VS, Thomas MJ, Proll S, Solórzano A, Billharz R, Fornek JL, Thomas S, Chen CH, Clark EA, Murali-Krishna K, Katze MG. Functional genomic and serological analysis of the protective immune response resulting from vaccination of macaques with an NS1-truncated influenza virus. J Virol 2007; 81:11817-27. [PMID: 17715226 PMCID: PMC2168783 DOI: 10.1128/jvi.00590-07] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We are still inadequately prepared for an influenza pandemic due to the lack of a vaccine effective for subtypes to which the majority of the human population has no prior immunity and which could be produced rapidly in sufficient quantities. There is therefore an urgent need to investigate novel vaccination approaches. Using a combination of genomic and traditional tools, this study compares the protective efficacy in macaques of an intrarespiratory live influenza virus vaccine produced by truncating NS1 in the human influenza A/Texas/36/91 (H1N1) virus with that of a conventional vaccine based on formalin-killed whole virus. After homologous challenge, animals in the live-vaccine group had greatly reduced viral replication and pathology in lungs and reduced upper respiratory inflammation. They also had lesser induction of innate immune pathways in lungs and of interferon-sensitive genes in bronchial epithelium. This postchallenge response contrasted with that shortly after vaccination, when more expression of interferon-sensitive genes was observed in bronchial cells from the live-vaccine group. This suggested induction of a strong innate immune response shortly after vaccination with the NS1-truncated virus, followed by greater maturity of the postchallenge immune response, as demonstrated with robust influenza virus-specific CD4+ T-cell proliferation, immunoglobulin G production, and transcriptional induction of T- and B-cell pathways in lung tissue. In conclusion, a single respiratory tract inoculation with an NS1-truncated influenza virus was effective in protecting nonhuman primates from homologous challenge. This protection was achieved in the absence of significant or long-lasting adverse effects and through induction of a robust adaptive immune response.
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Baas T, Baskin CR, Diamond DL, García-Sastre A, Bielefeldt-Ohmann H, Tumpey TM, Thomas MJ, Carter VS, Teal TH, Van Hoeven N, Proll S, Jacobs JM, Caldwell ZR, Gritsenko MA, Hukkanen RR, Camp DG, Smith RD, Katze MG. Integrated molecular signature of disease: analysis of influenza virus-infected macaques through functional genomics and proteomics. J Virol 2006; 80:10813-28. [PMID: 16928763 PMCID: PMC1641753 DOI: 10.1128/jvi.00851-06] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent outbreaks of avian influenza in humans have stressed the need for an improved nonhuman primate model of influenza pathogenesis. In order to further develop a macaque model, we expanded our previous in vivo genomics experiments with influenza virus-infected macaques by focusing on the innate immune response at day 2 postinoculation and on gene expression in affected lung tissue with viral genetic material present. Finally, we sought to identify signature genes for early infection in whole blood. For these purposes, we infected six pigtailed macaques (Macaca nemestrina) with reconstructed influenza A/Texas/36/91 virus and three control animals with a sham inoculate. We sacrificed one control and two experimental animals at days 2, 4, and 7 postinfection. Lung tissue was harvested for pathology, gene expression profiling, and proteomics. Blood was collected for genomics every other day from each animal until the experimental endpoint. Gross and microscopic pathology, immunohistochemistry, viral gene expression by arrays, and/or quantitative real-time reverse transcription-PCR confirmed successful yet mild infections in all experimental animals. Genomic experiments were performed using macaque-specific oligonucleotide arrays, and high-throughput proteomics revealed the host response to infection at the mRNA and protein levels. Our data showed dramatic differences in gene expression within regions in influenza virus-induced lesions based on the presence or absence of viral mRNA. We also identified genes tightly coregulated in peripheral white blood cells and in lung tissue at day 2 postinoculation. This latter finding opens the possibility of using gene expression arrays on whole blood to detect infection after exposure but prior to onset of symptoms or shedding.
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Husted TL, Neff G, Thomas MJ, Gross TG, Woodle ES, Buell JF. Liver transplantation for primary or metastatic sarcoma to the liver. Am J Transplant 2006; 6:392-7. [PMID: 16426326 DOI: 10.1111/j.1600-6143.2005.01179.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Sarcoma is generally a rare disease in the US, with poor survival in patients with both primary angiosarcoma and metastatic disease from sarcoma and GIST. In order to determine if liver transplantation for sarcoma is a realistic option, we examined records of all patients in the US component of the Israel Penn International Transplant Tumor Registry were reviewed. Those patients with liver failure from primary or metastatic liver sarcoma were evaluated. Patient outcome analysis was then performed. Patient and tumor demographics were reviewed as well as patient survival after transplantation. 19 patients are identified having received liver transplantation after treatment for sarcoma of the liver, 6 patients with primary hepatic sarcoma and 13 patients with metastatic sarcoma of the liver. Recurrence was almost universal in 18 of 19 patients (95%) after a median interval of 6 months. Survival for the group as a whole was 47% for 1-year, 15% for 3-years and 5% for 5-years. Given the early recurrence of tumor and meager 1-year survival outcome, liver transplantation is a poor therapeutic choice for patients with either primary or metastatic liver sarcoma, including high-grade leiomyosarcoma (GIST) regardless of primary site or primary therapy.
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Abstract
INTRODUCTION Left laparoscopic donor nephrectomy (LDN) is preferred over right LDN due to technical ease. The purpose of this study was to compare results between right and left LDN and thereby determine whether substantial experience with right LDN can provide results equivalent to left LDN. METHODS All LDN from 2000 to 2004 were reviewed, and right LDN data compared to left LDN data. Statistical analyses included chi-square and Student t tests. RESULTS Two hundred thirteen left LDN (84%) were compared to 40 right LDN (16%). Donor age, gender, race, and body mass index, and multiple arteries were similar in right and left LDN groups. Operative and cold ischemia times were similar, but warm ischemia was longer for right LDN (3:55 +/- 1:22 minutes) than left LDN (3.18 +/- 1:06 minutes; P = .004). Despite this, renal allograft function was similar on postoperative day 7 (creatinine 1.77 +/- 1.21 for right LDN, 1.7 +/- 1.5 for left LDN) and at 1 year (right LDN 1.5 +/- 0.4, left LDN 1.23 +/- 0.28). Graft survival rate in the right LDN at 1 year was 97.5%. CONCLUSIONS This large experience with right LDN indicates that results comparable to left LDN can be obtained. This observation increases the options for LDN in patients with multiple left renal arteries, or with right renal cysts, or with right kidneys that are smaller in size compared to the contralateral left kidney.
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Alloway RR, Hanaway MJ, Trofe J, Boardman R, Rogers CC, Hanaway MJ, Buell JF, Munda R, Alexander JW, Thomas MJ, Roy-Chaudhury P, Cardi M, Woodle ES. A prospective, pilot study of early corticosteroid cessation in high-immunologic-risk patients: the Cincinnati experience. Transplant Proc 2005; 37:802-3. [PMID: 15848537 DOI: 10.1016/j.transproceed.2004.12.129] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND The first prospective trial of steroid withdrawal dedicated to high-immunologic-risk patients is reported herein. METHODS Twenty-five patients were enrolled prospectively in an IRB-approved HIPAA-compliant protocol. Immunosuppression included corticosteroid withdrawal (CSWD) at 7 days, tacrolimus (target trough level 4 to 8 ng/mL), sirolimus (target trough level 8 to 12 ng/mL), and Mycophenolate Mofetil (2 g/d). Induction with daclizumab (2 mg/kg) on posttransplant days (PTD) 0 and 14 was administered to the first 10 patients. The protocol for the next 15 patients was modified because of high acute rejection rates to include received T-cell-depleting antibody induction therapy with thymoglobulin (1.5 mg/kg) on PTDs 0 and 2 followed by daclizumab on Postoperative day (POD) 14. Recipient inclusion criteria included: (1) repeat transplant recipients; or (2) patients with a peak PRA > or =25%. All rejection episodes were diagnosed by biopsy and graded using Banff '97 criteria. RESULTS Twenty-five patients were enrolled and median follow-up was 402 days. Forty percent of recipients were black, 68% of patients were repeat transplant recipients, 68% received deceased donor kidneys, and 36% had a peak flow PRA >25%. Overall acute rejection, graft survival, and patient survival rates of 40%, 88%, and 96%, respectively, were observed for the duration of the study. Acute rejection occurred in 6 of 10 patients (60%) with daclizumab induction; however, acute rejection rates fell to 27% when thymoglobulin was introduced (P = .1). CONCLUSIONS This study supports our previous observations in a multivariate analysis of early CSWD patients, wherein polyclonal antibody induction therapy reduced acute rejection. High-immunologic-risk patients may be able to undergo early CSWD with acceptable rates of acute rejection.
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Philipraj SJ, Thomas MJ, Gopalakrishnan G. Immediate or early alignment versus delayed management for posterior urethral injuries. Hippokratia 2005. [DOI: 10.1002/14651858.cd005404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Husted TL, Hanaway MJ, Thomas MJ, Woodle ES, Buell JF. Laparoscopic Living Donor Nephrectomy for Kidneys With Multiple Arteries. Transplant Proc 2005; 37:629-30. [PMID: 15848480 DOI: 10.1016/j.transproceed.2004.12.128] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Laparoscopic donor nephrectomy (LDN) involving kidneys with multiple arterial vessels is limited to a small number of reports, with all but two series reporting fewer than 25 patients. Moreover, outside of the pioneering centers at the University of Maryland and Johns Hopkins, no series of at least 25 patients has been published confirming these experience. The present study presents the largest series of LDN of donor kidneys with multiple arterial vessels outside of these two pioneering programs. METHODS All LDN performed at the University of Cincinnati from 2000 to 2004 were reviewed. Results between LDN kidneys with a single vessel and those with multiple vessels were compared. Statistical analysis included chi-square and Student t test. RESULTS Of 240 LDN, 37 were performed for kidneys with multiple vessels (15%): nine right kidneys (25%) and 28 left kidneys (75%). Cold ischemia time was longer for the multiple vessel organs (46 +/- 24 minutes) than for single vessel organs (35 +/- 13 minutes; P = .001), and warm ischemia time was longer for the multiple vessel kidneys (4:20 +/- 2:05 minutes) than single vessel kidneys (3:13 +/- 0:47 minutes; P = .001). Recipient renal function (serum creatinine) was similar for multiple and single artery donors at postoperative day 7 (1.76 +/- 1.38 and 1.7 +/- 1.47) and at postoperative day 365 (1.06 +/- 0.3 and 1.34 +/- 0.44). CONCLUSIONS This experience confirms results from other series in documenting the safety and reproducibility of LDN for kidneys with multiple arterial vessels.
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Finan PM, Thomas MJ. PI 3-kinase inhibition: a therapeutic target for respiratory disease. Biochem Soc Trans 2004; 32:378-82. [PMID: 15046612 DOI: 10.1042/bst0320378] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Asthma and COPD (chronic obstructive pulmonary disease) are a growing major health burden, which, despite improvements in disease management, still require new effective treatments. As our understanding of the cellular and molecular processes which govern respiratory diseases improves, the range of potential therapeutic targets increase. PI 3-kinases (phosphoinositide 3-kinases) are a family of closely related enzymes, which play pivotal roles in a diverse array of cellular mechanisms. In the present paper, we review the evidence for PI 3-kinase involvement in various cellular processes underlying asthma and COPD generated through inhibitor studies and gene-targeting approaches, and discuss the prospects for PI 3-kinase inhibition as a future therapeutic strategy for the treatment of respiratory disease.
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Eid T, Thomas MJ, Spencer DD, Rundén-Pran E, Lai JCK, Malthankar GV, Kim JH, Danbolt NC, Ottersen OP, de Lanerolle NC. Loss of glutamine synthetase in the human epileptogenic hippocampus: possible mechanism for raised extracellular glutamate in mesial temporal lobe epilepsy. Lancet 2004; 363:28-37. [PMID: 14723991 DOI: 10.1016/s0140-6736(03)15166-5] [Citation(s) in RCA: 298] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND High extracellular glutamate concentrations have been identified as a likely trigger of epileptic seizures in mesial temporal lobe epilepsy (MTLE), but the underlying mechanism remains unclear. We investigated whether a deficiency in glutamine synthetase, a key enzyme in catabolism of extracellular glutamate in the brain, could explain the perturbed glutamate homoeostasis in MTLE. METHODS The anteromedial temporal lobe is the focus of the seizures in MTLE, and surgical resection of this structure, including the hippocampus, leads to resolution of seizures in many cases. By means of immunohistochemistry, western blotting, and functional enzyme assays, we assessed the distribution, quantity, and activity of glutamine synthetase in the MTLE hippocampus. FINDINGS In western blots, the expression of glutamine synthetase in the hippocampus was 40% lower in MTLE than in non-MTLE samples (median 44 [IQR 30-58] vs 69 [56-87]% of maximum concentration in standard curve; p=0.043; n=8 and n=6, respectively). The enzyme activity was lower by 38% in MTLE vs non-MTLE (mean 0.0060 [SD 0.0031] vs 0.0097 [0.0042] U/mg protein; p=0.045; n=6 and n=9, respectively). Loss of glutamine synthetase was particularly pronounced in areas of the MTLE hippocampus with astroglial proliferation, even though astrocytes normally have high content of the enzyme. Quantitative immunoblotting showed no significant change in the amount of EAAT2, the predominant glial glutamate transporter in the hippocampus. INTERPRETATION A deficiency in glutamine synthetase in astrocytes is a possible molecular basis for extracellular glutamate accumulation and seizure generation in MTLE. Further studies are needed to define the cause, but the loss of glutamine synthetase may provide a new focus for therapeutic interventions in MTLE.
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Thomas MJ, Thomas M, Babu R, Velema J. Classification by objectives: a rejoinder. LEPROSY REV 2003; 74:175-6. [PMID: 12862260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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Thomas M, Thomas MJ. The changing face of rehabilitation in leprosy. INDIAN JOURNAL OF LEPROSY 2003; 75:143-52. [PMID: 15255401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
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Drewe E, Huissoon AP, Thomas MJ, Lanyon PC, Powell RJ. Recurrent fevers in the presence of multiple autoimmune diseases and antibody deficiency. Ann Rheum Dis 2002; 61:676-7. [PMID: 12117670 PMCID: PMC1754182 DOI: 10.1136/ard.61.8.676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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DeLong CJ, Baker PR, Samuel M, Cui Z, Thomas MJ. Molecular species composition of rat liver phospholipids by ESI-MS/MS: the effect of chromatography. J Lipid Res 2001; 42:1959-68. [PMID: 11734568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Using electrospray ionization tandem mass spectrometry (ESI-MS/MS) this study shows that the loss of glycerophospholipid (GPL) after chromatography was unevenly distributed across the GPL molecular species. Both TLC and HPLC caused a preferential loss of GPL with 0 to 3 double bonds: 20% and 7.2% for choline glycerophosphates (PC) and 19.7% and 7.5% for ethanolamine glycerophosphates (PE), respectively. A consequence of these losses was that GPLs containing fatty acids with four or more double bonds had a greater contribution to the total after chromatography. ESI-MS/MS analysis also showed that PC molecular species with four or more double bonds migrated at the front of the TLC band of PCs. GPLs extracted from TLC plates occasionally contained PCs that were smaller than those in the original extract. These low molecular mass PCs were easily reduced to alcohols and formed derivatives with 2,4-dinitrophenylhydrazine, suggesting that aldehydes were generated by the oxidation of unsaturated fatty acids. Directly analyzing lipid extracts by ESI-MS/MS without preliminary chromatographic separation gives an accurate distribution of GPL molecular species in lipid mixtures. However, the ionization of the phospholipids in the electrospray jet maximized at relatively low concentrations of GPL. There was a linear response between phospholipid mass and ion intensity for concentrations around 1-2 nmol/ml for both PC and PE. The total ion intensity continued to increase with concentrations above 1-2 nmol/ml, but the response was non-linear.
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Thomas MJ, Beurrier C, Bonci A, Malenka RC. Long-term depression in the nucleus accumbens: a neural correlate of behavioral sensitization to cocaine. Nat Neurosci 2001; 4:1217-23. [PMID: 11694884 DOI: 10.1038/nn757] [Citation(s) in RCA: 507] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A compelling model of experience-dependent plasticity is the long-lasting sensitization to the locomotor stimulatory effects of drugs of abuse. Adaptations in the nucleus accumbens (NAc), a component of the mesolimbic dopamine system, are thought to contribute to this behavioral change. Here we examine excitatory synaptic transmission in NAc slices prepared from animals displaying sensitization 10-14 days after repeated in vivo cocaine exposure. The ratio of AMPA (alpha-amino-3-hydroxy-5-methyl-4- isoxazole propionic acid) receptor- to NMDA (N-methyl-d-aspartate) receptor-mediated excitatory postsynaptic currents (EPSCs) was decreased at synapses made by prefrontal cortical afferents onto medium spiny neurons in the shell of the NAc. The amplitude of miniature EPSCs at these synapses also was decreased, as was the magnitude of long-term depression. These data suggest that chronic in vivo administration of cocaine elicits a long-lasting depression of excitatory synaptic transmission in the NAc, a change that may contribute to behavioral sensitization and addiction.
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Li HH, Thomas MJ, Pan W, Alexander E, Samuel M, Sorci-Thomas MG. Preparation and incorporation of probe-labeled apoA-I for fluorescence resonance energy transfer studies of rHDL. J Lipid Res 2001; 42:2084-91. [PMID: 11734582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Apolipoprotein A-I (apoA-I), the major constituent of HDL, plays an essential role in regulating cholesterol metabolism, acting as the physiological activator of lecithin: cholesterol acyltransferase, which converts cholesterol to cholesterol ester. Thiol-reactive fluorescent probes attached to cysteine-containing apoA-I mutants are currently being used to investigate the "LCAT active" conformation of lipid-bound apoA-I. Herein, we report new methodologies allowing rapid expression, fluorescent labeling, and recombinant HDL (rHDL) preparation for use in apoA-I in fluorescence resonance energy transfer (FRET) studies. Cysteine-containing mutant forms of human apoA-I were cloned into the pTYB12 vector containing a T7 promoter, a modified self-splicing protein element (intein), and a small affinity tag [chitin binding domain (CBD)]. The fusion proteins were expressed in Escherichia coli, isolated from cell lysates, and bound to a chitin-affinity column. Release of mature human apoA-I was initiated by the addition of DTT, which induced self-cleavage at the COOH terminus of the intein - CBD fusion protein. ApoA-I was further purified by Q-sepharose and then used for fluorescent probe labeling. Discoidal rHDL were then prepared with donor and/or acceptor labeled apoA-I and characterized with respect to their size, composition and ability to activate LCAT.
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